Dataset Information

Age-Related Changes in Quantitative Strain of Mouse Astrocytic Lamina Cribrosa and Peripapillary Sclera Using Confocal Microscopy in an Explant Model.

ABSTRACT:

Purpose

The purpose of this study was to measure the full-field deformation response to IOP change in the peripapillary sclera (PPS) and astrocytic lamina cribrosa (ALC) of young and old mouse eyes ex vivo.

Methods

Thirty-eight transgenic reporter mice with green fluorescent protein-expressing astrocytes were studied at 2 to 4 months and 13 to 15 months old. The ALC and PPS of the explant eyes were imaged using laser scanning microscopy under controlled inflation from 10 to 30 mm Hg. Strains were estimated for the ALC and PPS from imaged volumes using digital volume correlation.

Results

ALC strains were significantly greater than zero nasal-temporally for both age groups (mean = 4.3% and 4.0%; each P ? 0.004) and significantly greater than zero in the inferior-superior direction for younger mice (P = 0.0004). Younger mice had larger ALC inferior-superior strains than older mice (P = 0.002). The ALC area and perimeter enlarged with inflation in both age groups, with a greater increase in younger than in older mice (all P ? 0.004). The ALC nasal-temporal diameter change was greater than inferior-superiorly, and younger mice had greater enlargement nasal-temporally than older. PPS maximum shear strain was greater in the older mice (P = 0.002). The axial lengths of older mice were 14% longer and the PPS was 16% thinner than younger mice (both P = 0.0003).

Conclusions

The behavior of the ALC in younger mice with inflation exhibited greater strains and enlargement of ALC area than older mice. Some strain measures in the PPS were greater in older mice, likely related to their longer axial length and thinner PPS.

SUBMITTER: Nguyen C

PROVIDER: S-EPMC6516562 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Age-Related Changes in Quantitative Strain of Mouse Astrocytic Lamina Cribrosa and Peripapillary Sclera Using Confocal Microscopy in an Explant Model.

Nguyen Cathy C Midgett Dan D Kimball Elizabeth E Jefferys Joan J Nguyen Thao D TD Schaub Julie J Pease Mary M Quigley Harry H

Investigative ophthalmology & visual science 20181001 12

<h4>Purpose</h4>The purpose of this study was to measure the full-field deformation response to IOP change in the peripapillary sclera (PPS) and astrocytic lamina cribrosa (ALC) of young and old mouse eyes ex vivo.<h4>Methods</h4>Thirty-eight transgenic reporter mice with green fluorescent protein-expressing astrocytes were studied at 2 to 4 months and 13 to 15 months old. The ALC and PPS of the explant eyes were imaged using laser scanning microscopy under controlled inflation from 10 to 30 mm ...[more]

PMID: 30372742

Similar Datasets

Project description:This study investigated the inflation response of the lamina cribrosa (LC) and adjacent peripapillary sclera (PPS) in post-mortem human eyes with no history of glaucoma. The posterior sclera of 13 human eyes from 7 donors was subjected to controlled pressurization between 5-45 mmHg. A laser-scanning microscope (LSM) was used to image the second harmonic generation (SHG) response of collagen and the two-photon fluorescent (TPF) response of elastin within the volume of the LC and PPS at each pressure. Image volumes were analyzed using digital volume correlation (DVC) to calculate the three-dimensional (3D) deformation field between pressures. The LC exhibited larger radial strain, Err, and maximum principal strain, Emax, (p < 0.0001) and greater posterior displacement (p=0.0007) compared to the PPS between 5-45 mmHg, but had similar average circumferential strain, Eθθ, and maximum shear strain, Γmax. The Emax and Γmax were highest near the LC-PPS interface and lowest in the nasal quadrant of both tissues. Larger LC area was associated with smaller Emax in the peripheral LC and larger Emax in the central LC (p ≤ 0.01). The Emax, Γmax, and Eθθ in the inner PPS increased with increasing strain in adjacent LC regions (p ≤ 0.001). Smaller strains in the PPS were associated with a larger difference in the posterior displacement between the PPS and central LC (p < 0.0001 for Emax and Err), indicating that a stiffer pressure-strain response of the PPS is associated with greater posterior bowing of the LC. STATEMENT OF SIGNIFICANCE: Glaucoma causes vision loss through progressive damage of the retinal ganglion axons at the lamina cribrosa (LC), a connective tissue structure that supports the axons as they pass through the eye wall. It is hypothesized that strains caused by intraocular pressure may initiate this damage and that these strains are modulated by the combined deformation of the LC and adjacent peripapillary sclera (PPS). In this study we present a method to measure the pressure-induced 3D displacement and strain field in the LC and PPS simultaneously. Regional strain variation in the LC and PPS was investigated and compared and strains were analyzed for associations with age, LC area, LC strain magnitude, and LC posterior motion relative to the PPS.

Dataset Information

Age-Related Changes in Quantitative Strain of Mouse Astrocytic Lamina Cribrosa and Peripapillary Sclera Using Confocal Microscopy in an Explant Model.

Purpose

Methods

Results

Conclusions

Publications

Age-Related Changes in Quantitative Strain of Mouse Astrocytic Lamina Cribrosa and Peripapillary Sclera Using Confocal Microscopy in an Explant Model.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets